Ocean Harvesting Technologies AB - Experts & Thought Leaders

Latest Ocean Harvesting Technologies AB news & announcements

InfinityWEC shows significant improvement in energy output and motion control with moment-based MPC

Ocean Harvesting is currently developing generation 6 of its wave energy converter InfinityWEC in close collaboration with ball screw manufacturer NSK. A ball screw is a very good actuator providing a high ratio between linear motion and rotation to the generator, high efficiency, low weight and long life. However, ball screws are sensitive to the side forces and bending moments in the PTO caused by the surge motion of the buoy and high speeds that may occur in large waves. This challenge in the design of the PTO has been solved with a new linear guide system and increased control force. InfinityWECs simulation model Ocean Harvesting is now implementing and evaluating a moment-based MPC Ocean Harvesting is now implementing and evaluating a moment-based MPC (model predictive control) in InfinityWECs simulation model, showing significant improvement in energy output and computation time. Due to the increased control force, the velocity and stroke in the system can now be controlled and limited by the MPC, simplifying the design and making the system run more smoothly. The buoy can be pulled down and the PTO locked in a contracted state to avoid the highest loads in storm conditions. Advanced model predictive control algorithms "The combination of ball screw actuators with our hydrostatic pre-tension system is a very efficient solution to provide the control force needed in the PTO," says Mikael Sidenmark, CEO at Ocean Harvesting. He adds, "The solution benefits from the use of advanced model predictive control algorithms to optimise the force applied to the buoy in every given moment, resulting in both outstanding annual energy production and the ability to constrain the velocity and stroke in the PTO." Design for InfinityWEC generation 6 Mikael Sidenmark continues: "The new design provides very good operating conditions for the ball screws. We have increased from two to four ball screws to achieve a 25-year lifetime, thereby also increasing the peak force capacity from 1 to 2 MN, which in combination with the hydrostatic pre-tension provides higher control force than the buoyancy of the buoy." Focus in 2024 and early 2025 is the completion of the full-scale system design for InfinityWEC generation 6, implementation of the moment-based MPC algorithm in the control system, and preparation for the 1:3 scale sea trial project planned for 2025-2026. For these activities, Ocean Harvesting is raising 450,000 Euro in a financing round where new investors are invited.

Ocean Harvesting to raise funds for design update of InfinityWEC wave energy converter and preparation for sea trials

Ocean Harvesting Technologies AB has since 2017 been developing the wave energy converter - InfinityWEC. During 2023 and early 2024, the focus has been on the ball screw actuation system in the power take-off and refining simulation models for generation 6 of the technology.  Full-scale system design of InfinityWEC will continue in 2024, planned to be followed by a 1:3 scale sea trial project in 2025-2026. Ocean waves are a vast resource of renewable energy and wave power can produce electricity more consistently and at different times than wind- and solar power. This increases the value of produced electricity and reduces the energy storage needed to balance the grid or stand-alone facilities. InfinityWEC Energy production cost (LCOE) is estimated to be same competitive at 100 Euro/MWh already at 100 MW InfinityWEC is a novel wave energy converter with a breakthrough power take-off, providing very cost-efficient electricity production by maximising the energy output from every individual wave and producing up to 500 kW continuous power output. The energy production cost (LCOE) is estimated to be very competitive at 100 Euro/MWh already at 100 MW deployed capacity and <35 Euro/MW at GW scale deployment. “The ball screw actuators in the power take-off in combination with our hydrostatic pre-tension system is a very efficient solution,” says Mikael Sidenmark, CEO at Ocean Harvesting, adding “It benefits from the use of advanced model predictive control algorithms to optimise the force applied to the buoy in every given moment, which results in both outstanding annual energy production and the ability to control and reduce buoy motions and loads in the system.” InfinityWEC based on circularity by design principles InfinityWEC is based on circularity by design principles and achieves very high material efficiency and low environmental impact through the combination of high energy output and the use of low-cost and low-carbon materials. InfinityWEC is engineered for large-scale production and effective transports and logistics enabling efficient deployment of wave farms. Implementing new enhanced MPC algorithm Mikael Sidenmark continues: “Our focus in 2024 is the implementation of a new enhanced model predictive control (MPC) algorithm in the control system, and completion of the full-scale system design." He adds, "We will also bring forward our buoy technology as part of the ongoing EU-financed WECHull+ project. Preparations will continue for the 1:3 scale sea trial project planned for 2025-2026, for which a 2 million Euro grant has been approved by the Swedish Energy Agency.”

WECHULL+ project to develop novel floating structures based on high-performance concrete and Ocean Harvesting’s buoy design

The WECHULL+ project, co-ordinated by RISE Research Institutes of Sweden, has received a 2.5 MEUR grant from the EU Clean Energy Transition Partnership (CETP) program. The project will develop and test new floating structures of high-performance concrete, reducing cost and CO2 footprint, as well as improving circularity and reliability, in the offshore renewable energy sector. It is a 3-year project, starting in December 2023, implemented by a consortium of research organizations and companies from five European countries (RISE, Delft University of Technology, Carnegie Clean Energy, Ocean Harvesting Technologies, Gdansk University of Technology, SolarDuck, PLOCAN and Pekabex). Mature value chain Concrete structures are low cost, resistant to the marine environment, and are easy and fast to manufacture on-site (casting), in comparison to manufacturing of traditional steel structures. Concrete is the most used material in the world after water and has a mature value chain enabling local production worldwide. The solutions developed in the WECHULL+ project regarding material, modelling and design will be applicable for floating structures in ocean renewables and other areas. Ocean energy developers WECHULL+ is based on the excellent results and proof-of-concept from a previous project WECHULL+ is based on the excellent results and proof-of-concept from a previous project (WECHULL), where a new, highly flowable high-performance concrete mix was developed for Ocean Harvesting’s patented thin-walled honeycomb buoy.  The solution enables large-scale production on site and results in a buoy with a weight similar to a conventional steel hull, but at 4x lower cost, 3x lower CO2 footprint and 10x faster to manufacture. “Reducing the use of resources and the environmental impact are critical in the energy transition,” says Mikael Sidenmark, CEO Ocean Harvesting Technology. “We are very pleased that our honeycomb design for floating structures will also be tested by other ocean energy developers in sea trials, and we look forward to this collaboration.”

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